In terms of playing the game, lately I kind of bounce between alpha 1.2.6, 1.2.5, and 1.4.7. Depends on the mood.
In a1.2.6 (using
my own customizations) I was building a really long railway using my lattice blocks as a trestle, connecting my starting island base to a large house I built quite a ways away. I came to find that I may have to add powered track into that version since furnace carts don't have much oomph for large inclines.
In 1.2.5 (custom pack, typical Technic mods, along with Mystcraft, Thermal Expansion, Forestry, Thaumcraft 2, etc), I didn't disable any of the duplicate ores, and have intentionally avoided any kind of ore duplication or transmutation. I've been doing just fine, as a matter of fact! I've been trying to build up my MJ power infrastructure to run Forestry machines and quarries, and started my TC2 research. I'll probably go heavy on TC2 since I've never explored the mod fully and it would help in knowing what works/doesn't work properly in
Intermediary (whenever I get back to it).
In 1.4.7 (which I think is originally based off of the Direwolf20 pack, just modified), I haven't gotten that far into it, mostly lots of mining and a typical IC2 base. But I'll probably take advantage of stuff like Soul Shards and some of RP2's later features (wind mills, tube frames, etc) to do things I haven't done in a long while. I used to get so far in 1.4 packs then give up when the framerate would get terrible on my older machines at the time. So we'll see what I can get done nowadays.
I played modded 1.7.10 for a while but I'm not really feeling it anymore. I have a vanilla server as well that I did some server-side changes to but I'm bored of that already as well.